Derrick



G. F. WATTS.

DERRICK.

APPLICATION HLED JULYI3, I921.

Patented July 18, 1922.

4 SHEETS-SHEET I.

I .nmlh

G. F. WATTS.

DERRICK.

APPLICATION FILED JULY 13, 1921.

Patented July 18, 1922.

4 SHEETS-SHEET 2- F u 1. I

(lam we G. F. WATTS.

DERRICK.

APPLICATION HLED JULYIS, 1921,

Patented Juiy 18, 1922..

4 SHEETS-SHEET.3.

@f I i flrtorncu a. F. WATTS.

DERRICK.

' APPLICATION FILED JULYI3, 192T: 1,423,376, Patente July 18, @922.

4 SHEETS-SHEET 4.

STAT E GEORGE E. we'rrrs, on oston, MeSSACHUSETTs.

ER L FK- Application filed July 1 3, 1921. Serial No. 484;,458.

T 0 all w 710m it may concern Be it known that I. GEORGE F. \Vnrrs, a citizen of the United States, residing at the city of Boston, county of Suffolk. State of li lassachusett s, have invented new and useful Improvements in Derrichs. of which the fol lowing is a specification.

This invention relates to an improve ment in derricks. and more particularly to the foot'block and its application to and use with the mast.

The mast employed instructin'al work is generally'ot greatheight and ot consider able weight, and it has been found difiicult to rotate the mast for the purpose otcha-nging its position, as this is generally performed manually, due to the great amount of friction which is created at the base of the mast or the foot block. and the excessive weight of the mast and the loed which may be imposed on the mast and boom. It has been found by actual experience and use of the present invention that this ditliculty may overcome, and the-shifting or rotating of the mast may be accomplished with comparative ease and less manpower than heretofore.

A feature in the construction of the foot block, is to eliminate friction and to provide a support orbase for the mast where by the pressure on the ball race is evenly distributed regardless of the position oh the mast, whether the mast is perpendicular with respect to the foot block, or at an angle thereto. i I

' The foot block consists of a base'plate and a mast step, and the mast step is provided with a hub whichrotatably'fits an opening in the base plate thereby "affording a connection between the two members Interposed between the two members are ball bearings traveling in su'itab'leball races'on- V p v edge through which are 'ILO-CGlVGCl bolts 7, 7,

the respective members. i v

-(:ons'iderable stress imposed on the foot block, as the boom which is carried bythe mast "is el'evated,and the horizontal thrust of the boom transmitted to the 'ma st is takenc'aie of by the hub of the mast step entering into the base plate. It will therefore be recognized that the pressure exerted on the blocl rby themast froni either a perpendicular or angular direction is taken care of by the ball bearings, and the stress'transmitt'ed in a horizontal direction by the boom "is cared for by thchub 0n the mast step so that with all the pressure'and strain'imposed on the foot block it is constructed to skeleton mast and B the boom.

withstand. such conditions without binding or the creation of friction and permitting the mast to function properly.

' The invention consists of certain novel features of construction and combination oi parts which will be hereinafter described and pointed out in the claims.

In the accompanying drawings:

Figure 1 is a view in elevation showing the invention; Figure 2' is a detail view elevation and partly'in section showing the mast and boom supported on the foot block;

Figure Sis a detail view in vertical section of-the" mast and foot block;

Figure at isa. horizontal sectional view on line 4-4 of Figure 2;

Figure 5 is a perspective view of the lower end of. the boom;

Figure Gisa transverse vertical sectional vieWYon line 6-6 of Figure 2. showing the manner of attaching the boom to the mast;

"Figure 7 is a det'ailview in side elevation of'the lower terminal, of the mast; and

Figure 8 is a'perspective view of the locking plate employed for fastening the boom pin to the mast plate.

Referring" to the drawings it represents a These elements. the mast, and boom, are preferably tor the most part of standard construction.

' Suitable beams l. 1 are bolted together andinterposed betwccn thesebeams are sheaves 2 2. journalled on the shaft 8. extending through thc'beams l. A plate 4t ismounted on the shaft for supporting the two sheaves 2 and is heh'l against lateral movementby means 0'] bolts or rods I "lhe "toot-block is mounted upon the beams l and consists'oit a base plate 6 provided with a plurality of holes around the peripheral which passthrough the beams 1 for attaclr ing the'base plate thereto; Mountedupon the base plate is the maststep 8 having ahol- 1 hub member 9 which extends into an opening- 10 'f'tn'med inthe base-plate '6. A

bushihppll "encircies the hub for I l3,and' l t; respectively, in which are resheaves 2 i i 1 r i The lower end of the boom B, more par- ;t1cul arly shown in Figure 5. is reinforced by ceived a plurality of ball bearings 15 for forming an anti-friction bearing between the two members. The upper "face of the base plate 6 is also preferably hollowed out as at 16 for forming a lubricant receptacle whereby the balls will be properly lubricated.

The mast step 8 is provided on its upper surface with a plurality of vertical. ribs 17, 17, a pair of ribs being located on each side of the center of the mast step, and each-pair being in parallel relation. The space between the ribs or each pair being of like distances and depths. The central ribs are connected together by webs 18 while the outer ribs are provided with vertical webs 19 extending from the upper face of the mast step, whereby. the several ribs are properly braced and 'strengthened.

On two opposite sides of the mast A are attached plates 20. 20 by means of rivets 21. These plates extend beyond the lower end of the mast A and have attached thereto rein forcing plates 22 and 23. These plates 20 are provided with holes 'or elongated slots 24, as clearly shown in Figure? The plates 20 are received between the parallel rihsl'? and a slot 2 1 in each plate 20 is adapted to register with holes 25 in the'parallel ribs 17.

A pin26 passes through each pair of par allel ribs 17 and through the slots 24 ofthe plates 20 for attaching plate 20 between a pair of the ribs 17 and forming a-pivotal connection "for the mast A with the foot block and mast step 8. The pins 26 are provided with transverse slots 27 in which an edge 01 a locking plate 28is received. These locking plates 28 are attached by suitable screw bolts 29 to the outer faces of the outermost ribs 17 for holding the pins against longitudinal movement.

The connection of the mast A and the mast step 8 by the plates 20 is such that a suitable clearance is formed between the ribs 17, and

between the upper face of the mast step 8 and the plates 20. This clearance together with the slotted pin connection between the plates 20 and ribs 17. allows the mast-to de viate from a vertical. position without binding the ball race and the pressure on the ball race is always evenly distributed regardless of the position assumed by the mast. v This'construction makes provision for carrying the cables which operate the boom through the skeleton mast, the hollowhub 9 cab-the mast step 8 and thence over the means; of external plates 30 and angle iron suitable openings formed in the end of the boom plates 0 and partition plates 31 is a p n 32. Cotter pins 33 extend through the pin 32 on each side of the partition plates 31 for locking the pin against longitudinal movement, Plates 20 of the mast A are provided with lateral extensions 34 and these extensions are provided at their ends with open end slots 35 into which the ends of the pin 32 are received. The extensions 31 are preferably reinforced by filler plates 36 and angle iron plates '37. The ends of the filler plates 36 and angle iron plates 37 being slotted to conform to the slot in the lateral extension. A locking plate 39 provided with a hole to is employed for se curely attaching the boom to the mast. The hole 10 of the plates 39 receives the ends 01' the pin 32 and the plates 39 are bolted to the lateral extensions 34 whereby the boom is sesurely held in place.

The slots 35 in the lateral extensions M of the mast aflord a ready means of attaching the boom l3 toithc mast as the pin 32 01 the boom. cairbe readily inserted in the slots 35 and then by means of the locking plates the boom pin 32 isheld to the lateral extensions to prevent it from becoming disengaged therefrom. Q This connection eliminates the dilliculty. usually encountered in inserting a pin through openings formed in the mast and boom in attaching the boom to themast.

The hub 9 ofthe mast step 8 coactingwith the opening in the base plate 6 receives the thrust transmitted to the mast by the boom B, and prevents the possibility of the mast step being forced or caused to ride. over the ball bearings, which would occur if the hub was not provided on account of the heavy load carried by the boom. The greatest stress imparted to the mast by the boom The mast A is preferably located centrally of the maststepS so that the pressuref'of the mast will be exerted upon the ball bearings evenly. It is essential that thelmast be pivoted to the mast step because under different conditions ofuse of the boom the mast will be caused tomove one way or another, and as a result the pressure ofthe ball bearings, yet bythe central location of the mast, this pressure will be evenly distributed-among the several balls of the antifriction bearing, and the thrustot theboom will always be cared forby the hub 9;

The arrangement of the :several' parts of the derrickjhas been adopted .for'theipurpose of taking careof theapres sures .on the foot block by the mast and the stress is imparted thereto by the'boom so that it is possible to rotate and operate the derrick with the u greatest ease. partition plates 31. 31; Extending through Ithas been demonstrated with this construction that the mast may be rotated under the most trying conditions by one. man, whereas. at present with most ofthe derricks in useyit is either necessary to employ being when the boom is in a horizontal plane.

mast will be imparted to the mast step. and i several men to rotate the mast or to employ a block and tackle.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

1. The combination. of a foot-block consisting of a base plate and a mast step, antifrietion bearings interposed between the base plate and mast step, and a mast pivotally connected to the mast step and centrally located thereon, whereby the pressure exerted on the foot block by the mast regardless of its angle is equally distributed on the base plate by said anti-friction means.

2. The combination of a foot block including a base plate having a central opening and a mast step rotatably mounted thereon having a hub loosely fitted in the opening of the base plate, anti-friction bearings interposed between the base plate and mast step, and a mast pivotally connected to the mast step and centrally located thereon,

whereby the pressure exerted on the foot block by the mast regardless of its angle is equally distributed on the base plate by said anti-friction means.

3. The combination of a mast, a foot block, said foot block consisting of a base plate and a mast step, the base plate being provided with a central opening, a hollow hub on the mast step extending into the opening of the base plate, anti-friction bear ings interposed between the base plate andv mast step and plates carried by the mast and having pivotal connection with the mast step.

4t. The combination of a mast having openings in an end thereof, a foot block including a base plate having a central opeir ing, and a mast step rotatably mounted on the base plate provided with a hub extendinginto the opening of the base plate, antifriction bearings interposed. between the base plate and mast step, ribs on the mast step, and means passing through the ribs and the openings of the mast for pivotally connecting the mast to the mast step.

5. The combination of a mast having plates extending below the end thereof, said plates having slots therein, a base plate, a mast step rotatably mounted thereon, ribs on the mast step, a rib being located on each side of a mast plate, and means for pivotally connecting the mastplates to a pair of ribs.

6. In aderrick the combination of a mast, a foot block, including a base plate and a mast step rotatably mounted thereon, plates carried by the mast having pivotal conneetion with the mast step, said plates being provided with lateral extensions, which extensions are provided with slots. and a boom having a pin received in said slots of the lateral extensions for connecting the boom thereto.

enonen r. WATTS. 

